On Nov. 17, Chavez pleaded guilty to one count of transporting images of minors engaged in sexually explicit conduct according to a U.S. Immigration and Customs Enforcement (ICE) news release.

Chavez had images on his computer that showed nude girls appearing to be younger than 8 years old investigators said.

As part of his job, Chavez worked with special needs kids of elementary-school age in one-on-one instruction ICE agents said. He also supervised other children during recess and lunch periods and worked as a bus monitor accompanying some children to and from school officials said.

However, district police spokesperson said Chavez did not have unsupervised contact with students.

He worked in a special group that involved a small number fo students assisting them in reading according to Lt Rueben Littlejohn with San Diego Unified School District police department.

Littlejohn confirmed that Chavez has been fired from his job.

ICE investigators released his photo Tuesday asking for additional information from the public.

Littlejohn said Chavez had been a district employee since 1992 and had held various jobs over the 19 years with the district including bus monitor.

“To date, there is no hard evidence that any San Diego Unified school district students were victims of this child pornography,” he said. “However, we are appealing to the public asking for their assistance.”

Anyone who may have had previous contact with Chavez, or has information that may be relevant to the investigation, is asked to contact the case agent at (619) 744- 4625.

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